diff --git a/Lib/lib2to3/fixer_util.py b/Lib/lib2to3/fixer_util.py
index fefa612..37343c0 100644
--- a/Lib/lib2to3/fixer_util.py
+++ b/Lib/lib2to3/fixer_util.py
@@ -226,7 +226,7 @@
     """
     Check that something isn't an attribute or function name etc.
     """
-    prev = node.get_prev_sibling()
+    prev = node.prev_sibling
     if prev is not None and prev.type == token.DOT:
         # Attribute lookup.
         return False
diff --git a/Lib/lib2to3/fixes/fix_except.py b/Lib/lib2to3/fixes/fix_except.py
index dc2a5b1..5554c02 100644
--- a/Lib/lib2to3/fixes/fix_except.py
+++ b/Lib/lib2to3/fixes/fix_except.py
@@ -25,11 +25,11 @@
 from .. import pytree
 from ..pgen2 import token
 from .. import fixer_base
-from ..fixer_util import Assign, Attr, Name, is_tuple, is_list
+from ..fixer_util import Assign, Attr, Name, is_tuple, is_list, syms
 
 def find_excepts(nodes):
     for i, n in enumerate(nodes):
-        if isinstance(n, pytree.Node):
+        if n.type == syms.except_clause:
             if n.children[0].value == 'except':
                 yield (n, nodes[i+2])
 
diff --git a/Lib/lib2to3/fixes/fix_imports.py b/Lib/lib2to3/fixes/fix_imports.py
index 08be543..46ba4a2 100644
--- a/Lib/lib2to3/fixes/fix_imports.py
+++ b/Lib/lib2to3/fixes/fix_imports.py
@@ -27,6 +27,7 @@
            'ScrolledText': 'tkinter.scrolledtext',
            'Tkconstants': 'tkinter.constants',
            'Tix': 'tkinter.tix',
+           'ttk': 'tkinter.ttk',
            'Tkinter': 'tkinter',
            'markupbase': '_markupbase',
            '_winreg': 'winreg',
@@ -121,17 +122,18 @@
     def transform(self, node, results):
         import_mod = results.get("module_name")
         if import_mod:
-            new_name = self.mapping[import_mod.value]
+            mod_name = import_mod.value
+            new_name = self.mapping[mod_name]
             import_mod.replace(Name(new_name, prefix=import_mod.get_prefix()))
             if "name_import" in results:
                 # If it's not a "from x import x, y" or "import x as y" import,
                 # marked its usage to be replaced.
-                self.replace[import_mod.value] = new_name
+                self.replace[mod_name] = new_name
             if "multiple_imports" in results:
-                # This is a nasty hack to fix multiple imports on a
-                # line (e.g., "import StringIO, urlparse"). The problem is that I
-                # can't figure out an easy way to make a pattern recognize the
-                # keys of MAPPING randomly sprinkled in an import statement.
+                # This is a nasty hack to fix multiple imports on a line (e.g.,
+                # "import StringIO, urlparse"). The problem is that I can't
+                # figure out an easy way to make a pattern recognize the keys of
+                # MAPPING randomly sprinkled in an import statement.
                 results = self.match(node)
                 if results:
                     self.transform(node, results)
diff --git a/Lib/lib2to3/fixes/fix_itertools_imports.py b/Lib/lib2to3/fixes/fix_itertools_imports.py
index ede8ad9..8a57f6d 100644
--- a/Lib/lib2to3/fixes/fix_itertools_imports.py
+++ b/Lib/lib2to3/fixes/fix_itertools_imports.py
@@ -1,8 +1,9 @@
 """ Fixer for imports of itertools.(imap|ifilter|izip|ifilterfalse) """
 
 # Local imports
-from .. import fixer_base
-from ..fixer_util import BlankLine
+from lib2to3 import fixer_base
+from lib2to3.fixer_util import BlankLine, syms, token
+
 
 class FixItertoolsImports(fixer_base.BaseFix):
     PATTERN = """
@@ -11,34 +12,40 @@
 
     def transform(self, node, results):
         imports = results['imports']
-        children = imports.children[:] or [imports]
-        for child in children:
-            if not hasattr(child, 'value'):
-                # Handle 'import ... as ...'
-                continue
-            if child.value in ('imap', 'izip', 'ifilter'):
-                # The value must be set to none in case child == import,
-                # so that the test for empty imports will work out
+        if imports.type == syms.import_as_name or not imports.children:
+            children = [imports]
+        else:
+            children = imports.children
+        for child in children[::2]:
+            if child.type == token.NAME:
+                member = child.value
+                name_node = child
+            else:
+                assert child.type == syms.import_as_name
+                name_node = child.children[0]
+            member_name = name_node.value
+            if member_name in ('imap', 'izip', 'ifilter'):
                 child.value = None
                 child.remove()
-            elif child.value == 'ifilterfalse':
+            elif member_name == 'ifilterfalse':
                 node.changed()
-                child.value = 'filterfalse'
+                name_node.value = 'filterfalse'
 
         # Make sure the import statement is still sane
         children = imports.children[:] or [imports]
         remove_comma = True
         for child in children:
-            if remove_comma and getattr(child, 'value', None) == ',':
+            if remove_comma and child.type == token.COMMA:
                 child.remove()
             else:
                 remove_comma ^= True
 
-        if str(children[-1]) == ',':
+        if children[-1].type == token.COMMA:
             children[-1].remove()
 
         # If there are no imports left, just get rid of the entire statement
-        if not (imports.children or getattr(imports, 'value', None)):
+        if not (imports.children or getattr(imports, 'value', None)) or \
+                imports.parent is None:
             p = node.get_prefix()
             node = BlankLine()
             node.prefix = p
diff --git a/Lib/lib2to3/fixes/fix_set_literal.py b/Lib/lib2to3/fixes/fix_set_literal.py
index 414b1df..35743d2 100644
--- a/Lib/lib2to3/fixes/fix_set_literal.py
+++ b/Lib/lib2to3/fixes/fix_set_literal.py
@@ -38,7 +38,7 @@
         literal.extend(n.clone() for n in items.children)
         literal.append(pytree.Leaf(token.RBRACE, "}"))
         # Set the prefix of the right brace to that of the ')' or ']'
-        literal[-1].set_prefix(items.get_next_sibling().get_prefix())
+        literal[-1].set_prefix(items.next_sibling.get_prefix())
         maker = pytree.Node(syms.dictsetmaker, literal)
         maker.set_prefix(node.get_prefix())
 
diff --git a/Lib/lib2to3/fixes/fix_urllib.py b/Lib/lib2to3/fixes/fix_urllib.py
index 89abfc4..f262537 100644
--- a/Lib/lib2to3/fixes/fix_urllib.py
+++ b/Lib/lib2to3/fixes/fix_urllib.py
@@ -12,7 +12,7 @@
 MAPPING = {'urllib':  [
                 ('urllib.request',
                     ['URLOpener', 'FancyURLOpener', 'urlretrieve',
-                     '_urlopener', 'urlcleanup']),
+                     '_urlopener', 'urlopen', 'urlcleanup']),
                 ('urllib.parse',
                     ['quote', 'quote_plus', 'unquote', 'unquote_plus',
                      'urlencode', 'pathname2url', 'url2pathname', 'splitattr',
diff --git a/Lib/lib2to3/main.py b/Lib/lib2to3/main.py
index d37fe9e..084fc0c 100644
--- a/Lib/lib2to3/main.py
+++ b/Lib/lib2to3/main.py
@@ -10,8 +10,7 @@
 
 from . import refactor
 
-
-class StdoutRefactoringTool(refactor.RefactoringTool):
+class StdoutRefactoringTool(refactor.MultiprocessRefactoringTool):
     """
     Prints output to stdout.
     """
@@ -64,6 +63,8 @@
                       help="Fix up doctests only")
     parser.add_option("-f", "--fix", action="append", default=[],
                       help="Each FIX specifies a transformation; default: all")
+    parser.add_option("-j", "--processes", action="store", default=1,
+                      type="int", help="Run 2to3 concurrently")
     parser.add_option("-x", "--nofix", action="append", default=[],
                       help="Prevent a fixer from being run.")
     parser.add_option("-l", "--list-fixes", action="store_true",
@@ -126,7 +127,14 @@
         if refactor_stdin:
             rt.refactor_stdin()
         else:
-            rt.refactor(args, options.write, options.doctests_only)
+            try:
+                rt.refactor(args, options.write, options.doctests_only,
+                            options.processes)
+            except refactor.MultiprocessingUnsupported:
+                assert options.processes > 1
+                print >> sys.stderr, "Sorry, -j isn't " \
+                    "supported on this platform."
+                return 1
         rt.summarize()
 
     # Return error status (0 if rt.errors is zero)
diff --git a/Lib/lib2to3/patcomp.py b/Lib/lib2to3/patcomp.py
index f903125..7826f90 100644
--- a/Lib/lib2to3/patcomp.py
+++ b/Lib/lib2to3/patcomp.py
@@ -30,7 +30,7 @@
 
 def tokenize_wrapper(input):
     """Tokenizes a string suppressing significant whitespace."""
-    skip = (token.NEWLINE, token.INDENT, token.DEDENT)
+    skip = set((token.NEWLINE, token.INDENT, token.DEDENT))
     tokens = tokenize.generate_tokens(driver.generate_lines(input).__next__)
     for quintuple in tokens:
         type, value, start, end, line_text = quintuple
diff --git a/Lib/lib2to3/pytree.py b/Lib/lib2to3/pytree.py
index 1c09ef1..9de810e 100644
--- a/Lib/lib2to3/pytree.py
+++ b/Lib/lib2to3/pytree.py
@@ -1,7 +1,8 @@
 # Copyright 2006 Google, Inc. All Rights Reserved.
 # Licensed to PSF under a Contributor Agreement.
 
-"""Python parse tree definitions.
+"""
+Python parse tree definitions.
 
 This is a very concrete parse tree; we need to keep every token and
 even the comments and whitespace between tokens.
@@ -31,7 +32,8 @@
 
 class Base(object):
 
-    """Abstract base class for Node and Leaf.
+    """
+    Abstract base class for Node and Leaf.
 
     This provides some default functionality and boilerplate using the
     template pattern.
@@ -51,7 +53,8 @@
         return object.__new__(cls)
 
     def __eq__(self, other):
-        """Compares two nodes for equality.
+        """
+        Compare two nodes for equality.
 
         This calls the method _eq().
         """
@@ -60,7 +63,8 @@
         return self._eq(other)
 
     def __ne__(self, other):
-        """Compares two nodes for inequality.
+        """
+        Compare two nodes for inequality.
 
         This calls the method _eq().
         """
@@ -69,53 +73,58 @@
         return not self._eq(other)
 
     def _eq(self, other):
-        """Compares two nodes for equality.
+        """
+        Compare two nodes for equality.
 
-        This is called by __eq__ and __ne__.  It is only called if the
-        two nodes have the same type.  This must be implemented by the
-        concrete subclass.  Nodes should be considered equal if they
-        have the same structure, ignoring the prefix string and other
-        context information.
+        This is called by __eq__ and __ne__.  It is only called if the two nodes
+        have the same type.  This must be implemented by the concrete subclass.
+        Nodes should be considered equal if they have the same structure,
+        ignoring the prefix string and other context information.
         """
         raise NotImplementedError
 
     def clone(self):
-        """Returns a cloned (deep) copy of self.
+        """
+        Return a cloned (deep) copy of self.
 
         This must be implemented by the concrete subclass.
         """
         raise NotImplementedError
 
     def post_order(self):
-        """Returns a post-order iterator for the tree.
+        """
+        Return a post-order iterator for the tree.
 
         This must be implemented by the concrete subclass.
         """
         raise NotImplementedError
 
     def pre_order(self):
-        """Returns a pre-order iterator for the tree.
+        """
+        Return a pre-order iterator for the tree.
 
         This must be implemented by the concrete subclass.
         """
         raise NotImplementedError
 
     def set_prefix(self, prefix):
-        """Sets the prefix for the node (see Leaf class).
+        """
+        Set the prefix for the node (see Leaf class).
 
         This must be implemented by the concrete subclass.
         """
         raise NotImplementedError
 
     def get_prefix(self):
-        """Returns the prefix for the node (see Leaf class).
+        """
+        Return the prefix for the node (see Leaf class).
 
         This must be implemented by the concrete subclass.
         """
         raise NotImplementedError
 
     def replace(self, new):
-        """Replaces this node with a new one in the parent."""
+        """Replace this node with a new one in the parent."""
         assert self.parent is not None, str(self)
         assert new is not None
         if not isinstance(new, list):
@@ -138,7 +147,7 @@
         self.parent = None
 
     def get_lineno(self):
-        """Returns the line number which generated the invocant node."""
+        """Return the line number which generated the invocant node."""
         node = self
         while not isinstance(node, Leaf):
             if not node.children:
@@ -152,8 +161,10 @@
         self.was_changed = True
 
     def remove(self):
-        """Remove the node from the tree. Returns the position of the node
-        in its parent's children before it was removed."""
+        """
+        Remove the node from the tree. Returns the position of the node in its
+        parent's children before it was removed.
+        """
         if self.parent:
             for i, node in enumerate(self.parent.children):
                 if node is self:
@@ -162,10 +173,12 @@
                     self.parent = None
                     return i
 
-    def get_next_sibling(self):
-        """Return the node immediately following the invocant in their
-        parent's children list. If the invocant does not have a next
-        sibling, return None."""
+    @property
+    def next_sibling(self):
+        """
+        The node immediately following the invocant in their parent's children
+        list. If the invocant does not have a next sibling, it is None
+        """
         if self.parent is None:
             return None
 
@@ -177,10 +190,12 @@
                 except IndexError:
                     return None
 
-    def get_prev_sibling(self):
-        """Return the node immediately preceding the invocant in their
-        parent's children list. If the invocant does not have a previous
-        sibling, return None."""
+    @property
+    def prev_sibling(self):
+        """
+        The node immediately preceding the invocant in their parent's children
+        list. If the invocant does not have a previous sibling, it is None.
+        """
         if self.parent is None:
             return None
 
@@ -192,9 +207,11 @@
                 return self.parent.children[i-1]
 
     def get_suffix(self):
-        """Return the string immediately following the invocant node. This
-        is effectively equivalent to node.get_next_sibling().get_prefix()"""
-        next_sib = self.get_next_sibling()
+        """
+        Return the string immediately following the invocant node. This is
+        effectively equivalent to node.next_sibling.get_prefix()
+        """
+        next_sib = self.next_sibling
         if next_sib is None:
             return ""
         return next_sib.get_prefix()
@@ -205,7 +222,8 @@
     """Concrete implementation for interior nodes."""
 
     def __init__(self, type, children, context=None, prefix=None):
-        """Initializer.
+        """
+        Initializer.
 
         Takes a type constant (a symbol number >= 256), a sequence of
         child nodes, and an optional context keyword argument.
@@ -222,42 +240,44 @@
             self.set_prefix(prefix)
 
     def __repr__(self):
-        """Returns a canonical string representation."""
+        """Return a canonical string representation."""
         return "%s(%s, %r)" % (self.__class__.__name__,
                                type_repr(self.type),
                                self.children)
 
     def __str__(self):
-        """Returns a pretty string representation.
+        """
+        Return a pretty string representation.
 
         This reproduces the input source exactly.
         """
         return "".join(map(str, self.children))
 
     def _eq(self, other):
-        """Compares two nodes for equality."""
+        """Compare two nodes for equality."""
         return (self.type, self.children) == (other.type, other.children)
 
     def clone(self):
-        """Returns a cloned (deep) copy of self."""
+        """Return a cloned (deep) copy of self."""
         return Node(self.type, [ch.clone() for ch in self.children])
 
     def post_order(self):
-        """Returns a post-order iterator for the tree."""
+        """Return a post-order iterator for the tree."""
         for child in self.children:
             for node in child.post_order():
                 yield node
         yield self
 
     def pre_order(self):
-        """Returns a pre-order iterator for the tree."""
+        """Return a pre-order iterator for the tree."""
         yield self
         for child in self.children:
             for node in child.post_order():
                 yield node
 
     def set_prefix(self, prefix):
-        """Sets the prefix for the node.
+        """
+        Set the prefix for the node.
 
         This passes the responsibility on to the first child.
         """
@@ -265,7 +285,8 @@
             self.children[0].set_prefix(prefix)
 
     def get_prefix(self):
-        """Returns the prefix for the node.
+        """
+        Return the prefix for the node.
 
         This passes the call on to the first child.
         """
@@ -274,23 +295,29 @@
         return self.children[0].get_prefix()
 
     def set_child(self, i, child):
-        """Equivalent to 'node.children[i] = child'. This method also sets the
-        child's parent attribute appropriately."""
+        """
+        Equivalent to 'node.children[i] = child'. This method also sets the
+        child's parent attribute appropriately.
+        """
         child.parent = self
         self.children[i].parent = None
         self.children[i] = child
         self.changed()
 
     def insert_child(self, i, child):
-        """Equivalent to 'node.children.insert(i, child)'. This method also
-        sets the child's parent attribute appropriately."""
+        """
+        Equivalent to 'node.children.insert(i, child)'. This method also sets
+        the child's parent attribute appropriately.
+        """
         child.parent = self
         self.children.insert(i, child)
         self.changed()
 
     def append_child(self, child):
-        """Equivalent to 'node.children.append(child)'. This method also
-        sets the child's parent attribute appropriately."""
+        """
+        Equivalent to 'node.children.append(child)'. This method also sets the
+        child's parent attribute appropriately.
+        """
         child.parent = self
         self.children.append(child)
         self.changed()
@@ -306,10 +333,11 @@
     column = 0   # Column where this token tarts in the input
 
     def __init__(self, type, value, context=None, prefix=None):
-        """Initializer.
+        """
+        Initializer.
 
-        Takes a type constant (a token number < 256), a string value,
-        and an optional context keyword argument.
+        Takes a type constant (a token number < 256), a string value, and an
+        optional context keyword argument.
         """
         assert 0 <= type < 256, type
         if context is not None:
@@ -320,51 +348,53 @@
             self.prefix = prefix
 
     def __repr__(self):
-        """Returns a canonical string representation."""
+        """Return a canonical string representation."""
         return "%s(%r, %r)" % (self.__class__.__name__,
                                self.type,
                                self.value)
 
     def __str__(self):
-        """Returns a pretty string representation.
+        """
+        Return a pretty string representation.
 
         This reproduces the input source exactly.
         """
         return self.prefix + str(self.value)
 
     def _eq(self, other):
-        """Compares two nodes for equality."""
+        """Compare two nodes for equality."""
         return (self.type, self.value) == (other.type, other.value)
 
     def clone(self):
-        """Returns a cloned (deep) copy of self."""
+        """Return a cloned (deep) copy of self."""
         return Leaf(self.type, self.value,
                     (self.prefix, (self.lineno, self.column)))
 
     def post_order(self):
-        """Returns a post-order iterator for the tree."""
+        """Return a post-order iterator for the tree."""
         yield self
 
     def pre_order(self):
-        """Returns a pre-order iterator for the tree."""
+        """Return a pre-order iterator for the tree."""
         yield self
 
     def set_prefix(self, prefix):
-        """Sets the prefix for the node."""
+        """Set the prefix for the node."""
         self.changed()
         self.prefix = prefix
 
     def get_prefix(self):
-        """Returns the prefix for the node."""
+        """Return the prefix for the node."""
         return self.prefix
 
 
 def convert(gr, raw_node):
-    """Converts raw node information to a Node or Leaf instance.
+    """
+    Convert raw node information to a Node or Leaf instance.
 
-    This is passed to the parser driver which calls it whenever a
-    reduction of a grammar rule produces a new complete node, so that
-    the tree is build strictly bottom-up.
+    This is passed to the parser driver which calls it whenever a reduction of a
+    grammar rule produces a new complete node, so that the tree is build
+    strictly bottom-up.
     """
     type, value, context, children = raw_node
     if children or type in gr.number2symbol:
@@ -379,7 +409,8 @@
 
 class BasePattern(object):
 
-    """A pattern is a tree matching pattern.
+    """
+    A pattern is a tree matching pattern.
 
     It looks for a specific node type (token or symbol), and
     optionally for a specific content.
@@ -409,14 +440,16 @@
         return "%s(%s)" % (self.__class__.__name__, ", ".join(map(repr, args)))
 
     def optimize(self):
-        """A subclass can define this as a hook for optimizations.
+        """
+        A subclass can define this as a hook for optimizations.
 
         Returns either self or another node with the same effect.
         """
         return self
 
     def match(self, node, results=None):
-        """Does this pattern exactly match a node?
+        """
+        Does this pattern exactly match a node?
 
         Returns True if it matches, False if not.
 
@@ -440,7 +473,8 @@
         return True
 
     def match_seq(self, nodes, results=None):
-        """Does this pattern exactly match a sequence of nodes?
+        """
+        Does this pattern exactly match a sequence of nodes?
 
         Default implementation for non-wildcard patterns.
         """
@@ -449,7 +483,8 @@
         return self.match(nodes[0], results)
 
     def generate_matches(self, nodes):
-        """Generator yielding all matches for this pattern.
+        """
+        Generator yielding all matches for this pattern.
 
         Default implementation for non-wildcard patterns.
         """
@@ -461,7 +496,8 @@
 class LeafPattern(BasePattern):
 
     def __init__(self, type=None, content=None, name=None):
-        """Initializer.  Takes optional type, content, and name.
+        """
+        Initializer.  Takes optional type, content, and name.
 
         The type, if given must be a token type (< 256).  If not given,
         this matches any *leaf* node; the content may still be required.
@@ -486,7 +522,8 @@
         return BasePattern.match(self, node, results)
 
     def _submatch(self, node, results=None):
-        """Match the pattern's content to the node's children.
+        """
+        Match the pattern's content to the node's children.
 
         This assumes the node type matches and self.content is not None.
 
@@ -505,7 +542,8 @@
     wildcards = False
 
     def __init__(self, type=None, content=None, name=None):
-        """Initializer.  Takes optional type, content, and name.
+        """
+        Initializer.  Takes optional type, content, and name.
 
         The type, if given, must be a symbol type (>= 256).  If the
         type is None this matches *any* single node (leaf or not),
@@ -533,7 +571,8 @@
         self.name = name
 
     def _submatch(self, node, results=None):
-        """Match the pattern's content to the node's children.
+        """
+        Match the pattern's content to the node's children.
 
         This assumes the node type matches and self.content is not None.
 
@@ -561,7 +600,8 @@
 
 class WildcardPattern(BasePattern):
 
-    """A wildcard pattern can match zero or more nodes.
+    """
+    A wildcard pattern can match zero or more nodes.
 
     This has all the flexibility needed to implement patterns like:
 
@@ -573,7 +613,8 @@
     """
 
     def __init__(self, content=None, min=0, max=HUGE, name=None):
-        """Initializer.
+        """
+        Initializer.
 
         Args:
             content: optional sequence of subsequences of patterns;
@@ -641,7 +682,8 @@
         return False
 
     def generate_matches(self, nodes):
-        """Generator yielding matches for a sequence of nodes.
+        """
+        Generator yielding matches for a sequence of nodes.
 
         Args:
             nodes: sequence of nodes
@@ -744,7 +786,8 @@
 class NegatedPattern(BasePattern):
 
     def __init__(self, content=None):
-        """Initializer.
+        """
+        Initializer.
 
         The argument is either a pattern or None.  If it is None, this
         only matches an empty sequence (effectively '$' in regex
@@ -776,7 +819,8 @@
 
 
 def generate_matches(patterns, nodes):
-    """Generator yielding matches for a sequence of patterns and nodes.
+    """
+    Generator yielding matches for a sequence of patterns and nodes.
 
     Args:
         patterns: a sequence of patterns
diff --git a/Lib/lib2to3/refactor.py b/Lib/lib2to3/refactor.py
index c0ba196..b679db4 100755
--- a/Lib/lib2to3/refactor.py
+++ b/Lib/lib2to3/refactor.py
@@ -506,6 +506,63 @@
             yield ""
 
 
+class MultiprocessingUnsupported(Exception):
+    pass
+
+
+class MultiprocessRefactoringTool(RefactoringTool):
+
+    def __init__(self, *args, **kwargs):
+        super(MultiprocessRefactoringTool, self).__init__(*args, **kwargs)
+        self.queue = None
+
+    def refactor(self, items, write=False, doctests_only=False,
+                 num_processes=1):
+        if num_processes == 1:
+            return super(MultiprocessRefactoringTool, self).refactor(
+                items, write, doctests_only)
+        try:
+            import multiprocessing
+        except ImportError:
+            raise MultiprocessingUnsupported
+        if self.queue is not None:
+            raise RuntimeError("already doing multiple processes")
+        self.queue = multiprocessing.JoinableQueue()
+        processes = [multiprocessing.Process(target=self._child)
+                     for i in xrange(num_processes)]
+        try:
+            for p in processes:
+                p.start()
+            super(MultiprocessRefactoringTool, self).refactor(items, write,
+                                                              doctests_only)
+        finally:
+            self.queue.join()
+            for i in xrange(num_processes):
+                self.queue.put(None)
+            for p in processes:
+                if p.is_alive():
+                    p.join()
+            self.queue = None
+
+    def _child(self):
+        task = self.queue.get()
+        while task is not None:
+            args, kwargs = task
+            try:
+                super(MultiprocessRefactoringTool, self).refactor_file(
+                    *args, **kwargs)
+            finally:
+                self.queue.task_done()
+            task = self.queue.get()
+
+    def refactor_file(self, *args, **kwargs):
+        if self.queue is not None:
+            self.queue.put((args, kwargs))
+        else:
+            return super(MultiprocessRefactoringTool, self).refactor_file(
+                *args, **kwargs)
+
+
 def diff_texts(a, b, filename):
     """Return a unified diff of two strings."""
     a = a.splitlines()
diff --git a/Lib/lib2to3/tests/test_fixers.py b/Lib/lib2to3/tests/test_fixers.py
index 3dcabf9..5076854 100755
--- a/Lib/lib2to3/tests/test_fixers.py
+++ b/Lib/lib2to3/tests/test_fixers.py
@@ -3404,6 +3404,18 @@
         a = "from itertools import bar as bang"
         self.check(b, a)
 
+        b = "from itertools import izip as _zip, imap, bar"
+        a = "from itertools import bar"
+        self.check(b, a)
+
+        b = "from itertools import imap as _map"
+        a = ""
+        self.check(b, a)
+
+        b = "from itertools import imap as _map, izip as _zip"
+        a = ""
+        self.check(b, a)
+
         s = "from itertools import bar as bang"
         self.unchanged(s)
 
diff --git a/Lib/lib2to3/tests/test_pytree.py b/Lib/lib2to3/tests/test_pytree.py
index 61c592a..9dc6e07 100755
--- a/Lib/lib2to3/tests/test_pytree.py
+++ b/Lib/lib2to3/tests/test_pytree.py
@@ -306,36 +306,36 @@
         n2 = pytree.Node(1000, [])
         p1 = pytree.Node(1000, [n1, n2])
 
-        self.failUnless(n1.get_next_sibling() is n2)
-        self.assertEqual(n2.get_next_sibling(), None)
-        self.assertEqual(p1.get_next_sibling(), None)
+        self.failUnless(n1.next_sibling is n2)
+        self.assertEqual(n2.next_sibling, None)
+        self.assertEqual(p1.next_sibling, None)
 
     def testLeafNextSibling(self):
         l1 = pytree.Leaf(100, "a")
         l2 = pytree.Leaf(100, "b")
         p1 = pytree.Node(1000, [l1, l2])
 
-        self.failUnless(l1.get_next_sibling() is l2)
-        self.assertEqual(l2.get_next_sibling(), None)
-        self.assertEqual(p1.get_next_sibling(), None)
+        self.failUnless(l1.next_sibling is l2)
+        self.assertEqual(l2.next_sibling, None)
+        self.assertEqual(p1.next_sibling, None)
 
     def testNodePrevSibling(self):
         n1 = pytree.Node(1000, [])
         n2 = pytree.Node(1000, [])
         p1 = pytree.Node(1000, [n1, n2])
 
-        self.failUnless(n2.get_prev_sibling() is n1)
-        self.assertEqual(n1.get_prev_sibling(), None)
-        self.assertEqual(p1.get_prev_sibling(), None)
+        self.failUnless(n2.prev_sibling is n1)
+        self.assertEqual(n1.prev_sibling, None)
+        self.assertEqual(p1.prev_sibling, None)
 
     def testLeafPrevSibling(self):
         l1 = pytree.Leaf(100, "a")
         l2 = pytree.Leaf(100, "b")
         p1 = pytree.Node(1000, [l1, l2])
 
-        self.failUnless(l2.get_prev_sibling() is l1)
-        self.assertEqual(l1.get_prev_sibling(), None)
-        self.assertEqual(p1.get_prev_sibling(), None)
+        self.failUnless(l2.prev_sibling is l1)
+        self.assertEqual(l1.prev_sibling, None)
+        self.assertEqual(p1.prev_sibling, None)
 
 
 class TestPatterns(support.TestCase):